A messaging system is provided whereby a message indicative of an invitation to collaboratively execute an application can be sent from one of the computing object to an intermediary system whereby the message is multicast to the other ones of the plurality of computing objects. The invitation message can be accepted by the other computing objects to cause the first object to launch the corresponding application. The other computing objects also launch versions of the application and exchange addressing information with the first application so that a multiparty application execution can be established.